我在我的模型中有一个属性叫做Promotion，它的类型是一个标志enum叫做UserPromotion。枚举成员的显示属性设置如下:
[Flags]
public enum UserPromotion
{
None = 0x0,
[Display(Name = "Send Job Offers By Mail")]
SendJobOffersByMail = 0x1,
[Display(Name = "Send Job Offers By Sms")]
SendJobOffersBySms = 0x2,
[Display(Name = "Send Other Stuff By Sms")]
SendPromotionalBySms = 0x4,
[Display(Name = "Send Other Stuff By Mail")]
SendPromotionalByMail = 0x8
}
现在我想要能够在我的视图中创建一个ul来显示我的Promotion属性的选定值。这就是我到目前为止所做的但问题是，我如何在这里获得显示名称?
<ul>
@foreach (int aPromotion in @Enum.GetValues(typeof(UserPromotion)))
{
var currentPromotion = (int)Model.JobSeeker.Promotion;
if ((currentPromotion & aPromotion) == aPromotion)
{
<li>Here I don't know how to get the display attribute of "currentPromotion".</li>
}
}
</ul>
对于这个问题，我有两个解决方案。
第一个解决方案是从enum中获取显示名称。
public enum CourseLocationTypes
{
[Display(Name = "On Campus")]
OnCampus,
[Display(Name = "Online")]
Online,
[Display(Name = "Both")]
Both
}
public static string DisplayName(this Enum value)
{
Type enumType = value.GetType();
string enumValue = Enum.GetName(enumType, value);
MemberInfo member = enumType.GetMember(enumValue)[0];
object[] attrs = member.GetCustomAttributes(typeof(DisplayAttribute), false);
string outString = ((DisplayAttribute)attrs[0]).Name;
if (((DisplayAttribute)attrs[0]).ResourceType != null)
{
outString = ((DisplayAttribute)attrs[0]).GetName();
}
return outString;
}
<h3 class="product-title white">@Model.CourseLocationType.DisplayName()</h3>
第二个解决方案是从枚举名称中获取显示名称，但在开发人员语言中它被称为patch。
public static string SplitOnCapitals(this string text)
{
var r = new Regex(@"
(?<=[A-Z])(?=[A-Z][a-z]) |
(?<=[^A-Z])(?=[A-Z]) |
(?<=[A-Za-z])(?=[^A-Za-z])", RegexOptions.IgnorePatternWhitespace);
return r.Replace(text, " ");
}
<div class="widget-box pt-0">
@foreach (var item in Enum.GetNames(typeof(CourseLocationType)))
{
<label class="pr-2 pt-1">
@Html.RadioButtonFor(x => x.CourseLocationType, item, new { type = "radio", @class = "iCheckBox control-label" }) @item.SplitOnCapitals()
</label>
}
@Html.ValidationMessageFor(x => x.CourseLocationType)
</div>
在Aydin和Todd回答的基础上，下面是一个扩展方法，它还可以让您从资源文件中获得名称
using AppResources;
using System;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Reflection;
using System.Resources;
public static class EnumExtensions
{
public static string GetDisplayName(this Enum enumValue)
{
var enumMember= enumValue.GetType()
.GetMember(enumValue.ToString());
DisplayAttribute displayAttrib = null;
if (enumMember.Any()) {
displayAttrib = enumMember
.First()
.GetCustomAttribute<DisplayAttribute>();
}
string name = null;
Type resource = null;
if (displayAttrib != null)
{
name = displayAttrib.Name;
resource = displayAttrib.ResourceType;
}
return String.IsNullOrEmpty(name) ? enumValue.ToString()
: resource == null ? name
: new ResourceManager(resource).GetString(name);
}
}
然后像这样使用它
public enum Season
{
[Display(ResourceType = typeof(Resource), Name = Season_Summer")]
Summer
}
对于这个问题，我有两个解决方案。
第一个解决方案是从enum中获取显示名称。
public enum CourseLocationTypes
{
[Display(Name = "On Campus")]
OnCampus,
[Display(Name = "Online")]
Online,
[Display(Name = "Both")]
Both
}
public static string DisplayName(this Enum value)
{
Type enumType = value.GetType();
string enumValue = Enum.GetName(enumType, value);
MemberInfo member = enumType.GetMember(enumValue)[0];
object[] attrs = member.GetCustomAttributes(typeof(DisplayAttribute), false);
string outString = ((DisplayAttribute)attrs[0]).Name;
if (((DisplayAttribute)attrs[0]).ResourceType != null)
{
outString = ((DisplayAttribute)attrs[0]).GetName();
}
return outString;
}
<h3 class="product-title white">@Model.CourseLocationType.DisplayName()</h3>
第二个解决方案是从枚举名称中获取显示名称，但在开发人员语言中它被称为patch。
public static string SplitOnCapitals(this string text)
{
var r = new Regex(@"
(?<=[A-Z])(?=[A-Z][a-z]) |
(?<=[^A-Z])(?=[A-Z]) |
(?<=[A-Za-z])(?=[^A-Za-z])", RegexOptions.IgnorePatternWhitespace);
return r.Replace(text, " ");
}
<div class="widget-box pt-0">
@foreach (var item in Enum.GetNames(typeof(CourseLocationType)))
{
<label class="pr-2 pt-1">
@Html.RadioButtonFor(x => x.CourseLocationType, item, new { type = "radio", @class = "iCheckBox control-label" }) @item.SplitOnCapitals()
</label>
}
@Html.ValidationMessageFor(x => x.CourseLocationType)
</div>
我很抱歉这样做，但我不能使用任何其他的答案，也没有时间在评论中争论。
使用c# 6语法。
static class EnumExtensions
{
/// returns the localized Name, if a [Display(Name="Localised Name")] attribute is applied to the enum member
/// returns null if there isnt an attribute
public static string DisplayNameOrEnumName(this Enum value)
// => value.DisplayNameOrDefault() ?? value.ToString()
{
// More efficient form of ^ based on http://stackoverflow.com/a/17034624/11635
var enumType = value.GetType();
var enumMemberName = Enum.GetName(enumType, value);
return enumType
.GetEnumMemberAttribute<DisplayAttribute>(enumMemberName)
?.GetName() // Potentially localized
?? enumMemberName; // Or fall back to the enum name
}
/// returns the localized Name, if a [Display] attribute is applied to the enum member
/// returns null if there is no attribute
public static string DisplayNameOrDefault(this Enum value) =>
value.GetEnumMemberAttribute<DisplayAttribute>()?.GetName();
static TAttribute GetEnumMemberAttribute<TAttribute>(this Enum value) where TAttribute : Attribute =>
value.GetType().GetEnumMemberAttribute<TAttribute>(value.ToString());
static TAttribute GetEnumMemberAttribute<TAttribute>(this Type enumType, string enumMemberName) where TAttribute : Attribute =>
enumType.GetMember(enumMemberName).Single().GetCustomAttribute<TAttribute>();
}
